Vehicles, in particular remotely controlled toy model vehicles, such as models and other reduced-sized vehicles, are driven in a variety of conditions, sometimes requiring different power train operation. Such conditions might include maneuvering around obstacles, often requiring tight turns. Off-road conditions, as another example, may cause a wheel to lose traction, such as when crossing a wet or sandy patch, or to lose its purchase on uneven terrain.
To enhance maneuvering, an “open differential” may be incorporated into such vehicles to assist in equalizing the torque of a pair of driven wheels. A typical open differential has a gear box which allows the driven wheels of a pair to rotate at different relative rates. Allowing rotation of the wheels at different relative rates compensates for different travel distances of inner and outer wheels during a turn. The outer wheel can rotate more quickly than the inner wheel, thereby preventing or reducing sluggish handling, tire damage, and undue strain on the drive train.
To enhance all-terrain operation, a “locked differential” may be incorporated to offer prevent or reduce the effects of traction differences at each driven wheel of a pair. This is typically accomplished, by disabling or reducing the ability of the wheels to spin at different rates. When the differential is fully locked, the pair of driven wheel each turns at the same rate, without regard to differences between traction on the underlying terrain or between the loads on each wheel.
A “locking differential” has also been used to address the needs of maneuvering and operation on variable terrain. A locking differential may be switched between “open” and “locked” (fully or partially) modes of operation, as desired. However, previously available locking differentials have been complex, difficult to assemble and relatively expensive.